U.S. Pat. No. 4,778,325, by the inventors of the present application, and to which German Patent 36 02 201 corresponds, describes a shelf service apparatus for storage of rod-shaped material located in self-supporting pallet boxes. The pallet boxes can be lifted by supports on their end faces for movement, horizontally and vertically, by a crane bridge, which spans a storage rack system on which the cassettes can be placed. The crane bridge carries lifting devices which are capable of interengaging with the pallet boxes so that they can be lifted off shelf brackets or the like in a storage rack system, and transported from one location to another, or to a floor station in a gangway between the rack system.
Rack systems are also known in which racks are arranged longitudinally next to each other and in essential alignment, with brackets, such as pallet supports, extending transversely from major support posts of the racks, longitudinally of the major direction of the pallet boxes or cassettes. The storage rack structures are spaced from each other to define rack passageways or gangways in the space between adjacent racks. One or more transport wagons can be guided, for example on rails, for moving the pallet boxes from a storage location to a utilization station, for example a reloading station, cutting station or the like. The transport wagon has room for at least two adjacent pallet boxes, and is arranged to pass at least in part beneath the lowest ones of the support brackets of the racks. The crane forms a load transferring apparatus, and is movable in direct passageways or gangways as well as transversely to the longitudinal boxes to transfer pallet boxes between storage locations, between a storage location and a transport wagon and the like. The transport wagon, preferably, has a conveyor thereon so that a pallet box located on the transport wagon, for example deposited by the crane, can be moved on the transport wagon.
The transport wagon is movable between a position where it can be loaded by the crane and the utilization station, to transport pallet boxes or cassettes loaded thereon to and from the utilization station.
Storage and transfer systems, as well as methods of storing and transferring goods, are described also in German Patent Disclosure Document DE-OS 37 08 401, in which a pallet box which is to be stored in a storage system is to be transported by the transport wagon to a position where a next subsequent cassette is to be placed on the transport wagon. The next subsequent cassette carrying goods to be then processed is placed on the transport wagon, the transport wagon then moved to the position in which the first pallet to be stored is to be placed, and the crane then hoists the pallet box to its assigned storage location. Thereafter, the transport wagon moves, for example to the utilization station or the like, to deliver the subsequently placed pallet box thereto.
This is a complex and time-consuming arrangement. The transport wagon, which cannot move very quickly, has to move back and forth between a reception position and a storage position; likewise, the crane has to first move twice, first to a delivery position for the subsequent cassette, and then to the storage position for the previously handled pallet box or cassette; each time, the transport wagon must start and stop and the crane likewise must move, start, stop, and lift or drop its hoisting apparatus.